metallic objects which would complete the circuit.

It will be found convenient if the elements of the battery are
arranged upon a frame of some sort, by means of which they may be
raised or lowered all together, and supported at any desired height.

* * * * *




THE ACTION OF THE SILENT DISCHARGE ON CHLORINE.


Arguing from the fact that oxygen gas, when subjected to the silent
discharge, partially undergoes condensation into ozone, it seemed
possible, says Mr. H.M. Vernon, in the _Chemical News_, that other
elementary gases, as chlorine and bromine vapor, might undergo an
analogous change when subjected to the same treatment. A glass tube,
with a U-shaped index of fine bore glass tubing, was filled with
purified and dried chlorine. After passing a current of the gas
through the tube for some time, the end was sealed in the blowpipe
flame. The tube was then warmed slightly, and a few bubbles of gas
thus driven out. The end of the index tube dipped under strong
sulphuric acid saturated with chlorine gas, so that, on cooling, a
short column of the acid was drawn up. This served as an index for any
changes of volume which might take place in the chlorine in the tube.
A silent discharge of electricity was then passed. The volume of the
gas was observed to increase slightly, but afterward it remained quite
constant, even after the discharge had been passed for several hours.